The best CORSIA supplier is not the cheapest one. It is the supplier that can prove eligibility for your compliance period, hand over verifiable registry documentation, secure host-country authorisation where Article 6 applies, and commit to multi-year supply. For airline finance and sustainability teams, choosing a supplier is now a compliance decision, not a procurement afterthought.
The Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) has turned carbon credit purchasing into a board-level topic. First-phase obligations for 2024–2026 are already accruing, eligible supply is scarce, and the credits an airline cancels must survive audit by regulators and verifiers years later. A weak supplier choice shows up as a compliance gap, a budget overrun, or a delivery failure at exactly the wrong moment.
This guide explains, step by step, how to assess a CORSIA supplier, verify credit eligibility, and contract with confidence. It draws on the analysis in Econetix’s free 49-page workbook, The CORSIA Guide, which airlines use to quantify their own position route by route.
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What to look for in a CORSIA supplier: the short answer
When comparing CORSIA credit suppliers in 2026, evaluate six things in this order:
- Eligibility proof for your exact compliance period (CP1 2024–2026 or CP2 2027–2029), not just “ICAO-approved programme”.
- Registry documentation: serial numbers, issuance dates, project type and the permanent CORSIA eligibility label, independently verifiable.
- Host-country authorisation (Letter of Authorisation) with a corresponding adjustment, where Article 6 applies.
- Long-term supply capacity: forward and multi-year offtake, not spot-only.
- Transparent pricing against a published market reference, with all fees broken out.
- Access that fits the tranche — primary supply at source from a developer or asset manager for compliance-grade volume, an intermediary or trading house where you want aggregation, liquidity and diversification.
Why CORSIA eligibility matters before you buy a single credit
Not every credit from an ICAO-approved programme is CORSIA-eligible. Eligibility depends on the programme, the methodology, the credit vintage and the compliance period — and it tightens over time.
ICAO’s Technical Advisory Body (TAB) reviews carbon-crediting programmes and recommends which may supply CORSIA Eligible Emissions Units (EEUs). Approval is granted per programme with a defined scope, and it is reassessed each cycle. A credit that qualifies today is not automatically eligible tomorrow, and a programme being “approved” does not mean every credit it issues qualifies.
Which programmes are approved, and for which period?
The approved list differs by compliance period. As of mid-2026:
| Compliance period | Approved programmes | Eligible vintages |
|---|---|---|
| CP1 2024–2026 | 10 programmes ACR, ART, CAR, Global Carbon Council, Gold Standard, Isometric, Premium T‑VER, Verra VCS, plus the World Bank’s BioCarbon Fund ISFL and FCPF. | Emission reductions from 1 Jan 2021 to 31 Dec 2026; activity first crediting period from 1 Jan 2016. |
| CP2 2027–2029 | 4 approved to date ACR, ART, Gold Standard, Verra VCS — 25 programmes applied in the 2026 TAB cycle, so the pool starts narrower and criteria are sharpening. | Emission reductions from 1 Jan 2021 to 31 Dec 2029; activity start as CP1. |
Source: ICAO, “CORSIA Eligible Emissions Units”, and TAB assessment cycles (icao.int/CORSIA). The eligibility window extends into CP2 rather than resetting, so CP1-window vintages can remain usable where the programme and scope stay approved.
Practical tip
Always check the specific methodology, scope and vintage of an offered credit against the approval for the compliance period you are buying for — not just the programme name. This single check prevents most eligibility disputes.
What makes a CORSIA supplier credible
A credible CORSIA supplier — whether a developer, an asset manager or a trading house — does more than close a trade: it provides transparent documentation, supports your due diligence, secures or verifies authorisation, and plans supply across compliance periods. The distinction that matters is capability and accountability, not the label on the counterparty.
Assess any supplier against four capabilities:
1. Documentation and registry verification
The supplier should let you independently verify credit origin, registry records, project type, issuance dates, serial numbers, retirement status and the CORSIA eligibility label through recognised registries. If you cannot verify a serial number yourself, treat it as unverified. CORSIA eligibility is a registry attribute on the unit itself, not a certificate on paper.
2. Market and regulatory knowledge
Post-2027 eligibility and authorisation rules are still tightening, and the EU’s 17 July 2026 proposal to extend the EU ETS to some departing flights adds another layer. A credible supplier translates these changes into concrete procurement guidance, not vague reassurance.
3. Long-term supply and forward contracting
Ask whether the supplier can support procurement beyond the current compliance period. For larger fleets, multi-year offtake agreements aligned to a requirement that moves with the Sector’s Growth Factor, participation and regulation are usually the right structure.
4. Pricing transparency and compliance support
Prices, transaction costs and settlement terms should be broken out clearly. Strong suppliers also offer eligibility reviews, retirement assistance and reporting support, which reduces the internal load on finance and sustainability teams.
The four ways to buy CORSIA credits — and which supplier type fits
Airlines buy CORSIA credits through four channels: directly from a project developer or asset manager, through intermediaries and commodity trading houses, on trading platforms, or via RfP consultants. None is better in the abstract — each trades risk, price, liquidity and volume differently, and most large buyers use several in combination.
Here is how the four channels compare on the three things a buyer actually pays for — risk, price and volume availability:
| Channel | Risk | Price | Volume availability |
| Project developer / asset manager (direct) | Delivery, issuance and country risk sit with a counterparty that also controls the asset — so it can manage them at source | Lowest at the primary level: you contract without a resale margin | High for future vintages via offtakes |
| Intermediaries / commodity trading houses | Actively managed: diversification across projects, replacement clauses, hedging and market-making | Includes a service margin, priced against deep market intelligence and liquidity | Highest: aggregated across countries, programmes and vintages |
| Trading platforms / exchanges | Low on settlement; no recourse on project quality | Transparent screen price (e.g. CIX) | Low today: thin listed CORSIA volume |
| RfP consultants / procurement events | Low: competitive tension, standardised terms | Market-tested via competition | Depends on RfP size; allocation not guaranteed |
Source: Econetix consolidation of the IATA CORSIA airline handbook supplier taxonomy (project developers, brokers, aggregators, retail/wholesale).
Project developer / asset manager
Pros: primary-level pricing without a resale margin, has deep market intelligence, first access to new vintages, and — where the developer is also the asset manager — one accountable party for eligibility, authorisation and delivery. Cons: exposure is concentrated in one counterparty and one project pipeline. Buyer tip: use offtake agreements with milestone payments tied to the Letter of Authorisation, issuance and CORSIA tagging; this channel especially rewards early, forward-contracted buyers.
Intermediaries and commodity trading houses
Pros: volume aggregated across many projects and host countries, deep market intelligence and liquidity, structured contracts with replacement clauses, and hedging — plus the balance-sheet capacity that keeps supply moving. Cons: a service margin sits on top of the primary price. Buyer tip: value a delivered track record and genuine market coverage over brochure breadth, and use the diversification to spread host-country risk.
Trading platforms and exchanges
Pros: price transparency, fast settlement and small clip sizes make screens useful for benchmarking and topping up. Cons: listed CORSIA volume today is a fraction of first-phase needs, and there is no recourse on project quality. Buyer tip: use the screen for price discovery and to true-up volumes, not as your primary supply line for large tranches.
RfP consultants and procurement events
Pros: competitive tension delivers market-tested pricing and strong documentation discipline, with standardised terms across bidders. Cons: the process takes months, and in a thin market an RfP can come back under-subscribed. Buyer tip: run eligibility-first RfPs with clear volume bands and delivery windows so bidders can price against a defined requirement.
The bottom line on channels
The supply chain only works as one chain: developers originate and authorise, trading houses and intermediaries aggregate, finance and move volume, and airlines cancel — each link adds value the others cannot. The practical question is not developer versus trader, but how close you need to sit to the primary asset for a given tranche. For opportunistic or diversified volume, an intermediary or trading house with strong market coverage is often the efficient choice; for compliance-grade, long-dated volume, contracting at source with a developer or asset manager secures price and first access to new vintages. Most sophisticated buyers combine both.
Key documents to check before buying CORSIA credits
Before any CORSIA purchase, request and review the project documentation, the registry record, and — where Article 6 applies — the host-country Letter of Authorisation with its corresponding adjustment.
Project documentation
Review project descriptions and verification reports to understand how the reductions were achieved and verified, and to screen for integrity concerns such as reversal or invalidation risk.
Letter of Authorisation (LoA) and Article 6
A Letter of Authorisation is the host-country attestation that a reduction may be used internationally under Article 6 of the Paris Agreement, backed by a corresponding adjustment so the same tonne is not counted twice. It must be publicly available before the units are used in CORSIA. LoA requirements are not universal — they apply where a host country has authorised specific reductions for international transfer — and they vary by programme, vintage and compliance period.
At the procurement stage, confirm:
- The specific credits carry the authorisation required for CORSIA compliance.
- Which authority issued the authorisation.
- The vintage and programme the authorisation covers.
How the authorisation aligns with your fleet’s obligation and the relevant compliance period.
Article 6 vs CORSIA: the distinction that matters for procurement
Article 6 of the Paris Agreement is the inter-governmental transfer mechanism; CORSIA is the aviation compliance scheme that uses credits authorised under it. The link between them is the corresponding adjustment, and it is where most long-dated procurement risk sits.
Under Article 6, countries can transfer mitigation outcomes (ITMOs) with corresponding adjustments so the same reduction is not counted in two national inventories. For CORSIA, that adjustment is what makes an authorised credit defensible. When buying for long-dated obligations, ask the supplier to confirm explicitly that the credits are backed by host-country authorisation and designed to meet ICAO requirements as they are amended — because ICAO is tightening corresponding-adjustment expectations after 2027.
Why supply is scarce, and why that matters to buyers
Roughly 300 Mt of credits are potentially first-phase eligible, but only about 38 Mt have become tagged CORSIA units — against projected CP1 demand near 163 Mt. Authorisation is a sovereign act, and only a handful of host countries can currently issue an LoA and carry the corresponding adjustment through a Biennial Transparency Report. Supply, not demand, is the bottleneck — which is why supplier access and early contracting decide price and certainty.
How to compare the top CORSIA suppliers in 2026
Compare suppliers on evidence, not rankings or marketing claims. Ask every shortlisted supplier the same due-diligence questions and score the answers.
Use this checklist:
- Can the supplier demonstrate credit eligibility for your specific compliance period (CP1 or CP2)?
- Does it provide full registry documentation you can verify independently?
- Are Letters of Authorisation available where Article 6 applies?
- Does it have aviation clients and a track record of delivery?
- Can it sustain long-term, forward-contracted supply?
- Is pricing transparent and benchmarked to a published market reference?
- Does it hold strong relationships across multiple project developers and registries, or develop and manage the assets itself — and is that reach matched by delivered volume?
Can it explain how its supply is positioned for post-2027 eligibility changes?
When should airlines buy CORSIA credits?
Earlier is cheaper and safer. CP1 obligations are already accrued and quantifiable, eligible supply is thin, and the compliance clock is fixed.
The first-phase deadlines are hard: states notify final offsetting requirements by 30 November 2027, and eligible units must be cancelled by 31 January 2028. Airlines that contract early keep negotiating leverage and first claim on the limited tagged pipeline; those that wait for the deadline compete for scarce supply with the least leverage. The market has already begun repricing on the back of the EU’s July 2026 proposal, which reinforces the case for locking volume before mandatory Phase 2 demand from 2027 competes for the same units.
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How Econetix supports credible CORSIA credit sourcing
Econetix is a carbon asset manager and project developer with 10 CORSIA-eligible projects delivering 4.5 Mt for CP1, supplying airlines and commodity trading houses directly at source.
As an IATA CORSIA Supporting Alliance partner working with host-country authorities from the DR Congo to Uganda and Rwanda, Econetix sits at the primary level of the supply chain: it helps buyers understand programme- and vintage-level eligibility, reviews project documentation, and navigates authorisation and registry verification. Because Econetix originates and manages its own assets, both airlines and commodity trading houses can source primary volume from the portfolio, with support for multi-year procurement planning into the second compliance period.
That combination — verified primary supply, transparent documentation and long-dated capacity — is what buyers and trading partners look for when they need eligible volume they can stand behind at audit.
Conclusion
Choosing the best CORSIA supplier is a matter of documentation quality, eligibility verification, market expertise and long-term supply capacity — not price alone. A structured procurement process reduces compliance risk, improves budget predictability and strengthens supply-chain integrity. Verify the registry records, confirm eligibility for the applicable CORSIA phase, understand the authorisation obligations, and contract early with a credible supplier such as Econetix.
Frequently Asked Questions (FAQs)
How should a CFO benchmark CORSIA suppliers beyond price?
Benchmark suppliers on four evidence-based criteria: registry documentation you can verify independently, eligibility proof for your specific compliance period, host-country authorisation where Article 6 applies, and forward supply capacity. Price alone ignores procurement-timing risk and long-term supply constraints, which are the larger cost drivers in a scarce market.
Are all carbon credits eligible under CORSIA?
No. Only credits that meet ICAO’s approved-programme, methodology and vintage criteria for the relevant compliance period qualify as CORSIA Eligible Emissions Units. Eligibility differs between CP1 (2024–2026) and CP2 (2027–2029) and is reassessed by ICAO’s Technical Advisory Body each cycle.
Which carbon programmes are CORSIA-approved for 2024–2026?
Ten programmes are approved for the first phase: American Carbon Registry (ACR), Architecture for REDD+ Transactions (ART), Climate Action Reserve (CAR), Global Carbon Council, Gold Standard, Isometric, Premium T-VER, Verra VCS, and the World Bank’s BioCarbon Fund ISFL and FCPF. For 2027–2029, four are approved to date: ACR, ART, Gold Standard and Verra VCS.
What is a Letter of Authorisation (LoA) in CORSIA?
A Letter of Authorisation is the host country’s attestation, under Article 6 of the Paris Agreement, that specific emission reductions may be used internationally, backed by a corresponding adjustment that prevents double counting. It must be publicly available before the units are used in CORSIA. It is required where Article 6 applies and varies by programme, vintage and compliance period.
How can airlines verify CORSIA eligibility before buying?
Check the registry record (serial numbers, issuance dates, retirement status and the CORSIA eligibility label), the project documentation and verification reports, the ICAO programme eligibility list for the relevant period, and the authorisation documents where required — all before purchase.
When is the CP1 cancellation deadline?
For the first compliance period (2024–2026), states notify final offsetting requirements by 30 November 2027 and eligible units must be cancelled by 31 January 2028. Buying early protects both price and supply certainty.
What is the difference between a project developer, a trading house and an RfP consultant for CORSIA credits?
A project developer (or asset manager) originates and controls the underlying mitigation activity and sells at the primary level — primary pricing and first access to new vintages, with risk concentrated in one pipeline. A commodity trading house or intermediary aggregates volume across many projects and adds market intelligence, liquidity, hedging and diversification for a service margin. A trading platform offers screen-price transparency but thin listed CORSIA volume. An RfP consultant runs a competitive procurement process. Each adds distinct value, and most large buyers combine them.
Should airlines buy CORSIA credits directly from a project developer or through a trading house?
Both have a place. For forward and multi-year, compliance-grade volume, buying at source from a developer or asset manager secures primary pricing and first access to future vintages, with eligibility, authorisation and delivery in one accountable counterparty. For diversified or opportunistic volume, a trading house or intermediary offers aggregation across host countries, liquidity and risk structuring that a single-project relationship cannot. The right answer usually blends the two; the key safeguard on any direct offtake is milestone payments tied to the Letter of Authorisation, issuance and CORSIA tagging.
How does Econetix help with CORSIA credit sourcing?
Econetix is a carbon asset manager and developer with 10 CORSIA-eligible projects delivering 4.5 Mt for CP1. It sits at the primary level of the supply chain, so airlines and commodity trading houses can source primary volume from the portfolio, with support for eligibility verification, registry documentation, host-country authorisation and multi-year procurement planning.
